ARC EXTINGUISHING DEVICE WITH A HIGH SPEED WHIP

摘要

Rapid arc extinguishing devices for air break switches have a whip with at least an end portion of nonmetallic material such as fiber reinforced plastic with a conductive path on its surface. The nonmetallic material is a single tapered rod or an assembly of a plurality of rods successively inserted into an outer rod. The conductive path on the whip is of various individual and combination forms of which some include a metal braid, foil, sheath or wound wire. Particular forms of the conductive path on the rod have enhanced durability and arc resistance at the areas of the whip most likely to be subject to arcing with a latch of the device upon switch opening or closing. Further forms of the whip are a combination in which an end portion as described is attached to an all metal base portion that is arranged to include a portion of the whip subject to arcing on switch closing. Another form of device has a latch engaging a whip at a rotating wheel on the latch. Whips with conductors having metal strands are made with strands bonded to the nonmetallic rod surface for greater durability in use. Whips with an all metal base portion have a metal spine within its nonmetallic portion through the joint region between the two portions, to minimize risk of damage to the nonmetallic portion from highstress in that region when such a whip is released from a latch. Also, a latch with a wheel or roller is improved by a design that limits wear of the conductive path on a nonmetallic rod surface.